FINALISTS

Six ideas to move the world toward a sustainable future

These social entrepreneurs were the 2011 finalists:

• Nick Christy (Winner), 39, of Australia, whose Water Recycling Shower cuts water and energy use and costs by 70 per cent without sacrificing enjoyment or hygiene by heating water as needed and sterilising it before reuse.

• Eden Full (Runner-up), 19, of Canada, whose SunSaluter, a $10 bamboo and metal rotator, boosts solar panels' effectiveness by 40 per cent by tilting them toward the sun;

• Sweden's Svante Bengtsson, 40, whose Rehact cooling, warming and ventilation system for buildings cuts energy use by 85 per cent by transferring air between inside and outside;

• Andreas Zachariah, 40, of the United Kingdom, whose smartphone app Carbon Diem detects the user's mode of transport, calculates CO2 emissions and suggests alternatives, raising travellers'  awareness so they can alter their behaviour;

• Dutchwoman Marjolein Helder, 28, whose natural electricity-generating system Plant-e uses electrodes to harvest continuous power from live plants grown in a bed of activated carbon and water; and

• Dutchman Peter van Dommele, 49, whose 4-D Kameleon system of rotating cartridges can be installed on building surfaces to absorb solar energy, collect rainwater, reduce CO2 and display messages;

High resolution images of our finalists can be downloaded in our online press room.